1. Field of the Invention
The present invention relates generally to a method of producing a filtering material practically employable in various application fields including a sanitary material such as a mask or the like, a deodoring filter to be incorporated in various kinds of deodoring units and a foodstuff packing material having sterilizing and deodoring functions. More particularly, the present invention relates to a method of producing a filtering material having a capability of adsorptively capturing very fine infectious or antigenous particles such as virus, bacteria or the like.
2. Description of the Related Art
The applicant common to the present invention has already proposed a method of producing a filtering material capable of adsorptively capturing virus under Japanese Patent Application Nos. 278487/1990 and 29301/1991. An outline of each of the prior inventions is such that a predetermined quantity of porous apatite particles and a predetermined quantity of water soluble glucan are dispersively dissolved in water to prepare an aqueous treatment solution, a sheet-shaped raw material is dipped in the treatment solution or it is coated with the same by employing a spraying process so as to allow it to be impregnated with the treatment solution, and thereafter, the sheet-shaped raw material having the treatment solution coated thereon is dried.
In spite of the already proposed methods of which excellent filtering property has been proven by repeated practical use, the applicant additionally conducted a series of development works for a filtering material having a more excellent filtering property and has reached the present invention.